Grain treating operations

ABSTRACT

An agitating and transport and heating process adjusted to a non-oxidizing flame provide inexpensive yet reliable and safe grain drying, using improved contact of the heating gases and the solid particulate material.

Sept. 3, 1874 L. M. TRIPLETT GRAIN TREATING OPERATIONS 3 Sheets-Shut 1 Original Filed Dec. 27, 1971 p 1974 L.M.1 RIPLETT GRAIN TREATING OIERATIQNS 3 Sheets-Shoot 2 Original Filed Dec.

F IG. 4

I I l I l I J {lllllll Sept. 3, 1974 1... M. TRIPLETT GRAIN TREATING OPERATIONS 3 Sheets-"Shoot 3 Original Filed Dec. 27, 1971 F/G/O United States Patent O 3,833,749 GRAIN TREATING OPERATIONS Lloyd M. Triplett, Rte. 1, Claude, Tex. 79019 Original application Dec. 27, 1971, Ser. No. 212,131, new Patent No. 3,741,717, dated June 26, 1973. Divided and this application Jan. 22, 1973, Ser. No. 325,316 Int. Cl. A231 1/18 US. Cl. 426-450 Claims ABSTRACT OF THE DISCLOSURE An agitating and transport and heating process adjusted to a non-oxidizing flame provide inexpensive yet reliable and safe grain drying, using improved contact of the heating gases and the solid particulate material.

CROSS REFERENCE TO RELATED APPLICATIONS This application is a division of my co-pending application Ser. No. 212,131, filed Dec. 27, 1971, now US. Pat. 3,741,717, issued June 26, 1973.

BACKGROUND OF THE INVENTION (1) Field of the Invention The field of art to which the invention pertains are, in foods and beverages, processes of cereal pufiing; in drying and gas or vapor contact with solids apparatus with axially rotating drums foramenous distributors and countercurrent flow and processes with treated material motion.

(2) Description of the Prior Art Grain drying apparatuses using flame to develop heat to dry out moist grain involve fire risk and suffer from poor heat transfer from heating gas to heated grain particle.

SUMMARY OF THE INVENTION In use of concentric drums, perforated to improve heat transfer and helically corrugated to expedite longitudinal movement of the to-be-treated solid, a non-oxidizing gas is provided with location of the zones for heating the treating gas spatially removed from the path of heated grain and related material and a multi-sectioned drum shape is used to provide a substantially continuous and complete contact of the major portion of heating gas and the to-be-heated solid particles.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic longitudinal vertical sectional view of one embodiment of apparatus according to this invention.

FIG. 2 is an oblique front and left end view from the left end of the apparatus of FIG. 1.

FIG. 3 is an oblique rear and end view from the right end of the apparatus of FIG. 1.

FIG. 4 is a schematic longitudinal vertical sectional view of another embodiment of apparatus, 220, according to this invention. FIG. 4 shows the drum 110 in vertical longitudinal section of plane 4A4A of FIG. 9.

FIG. 5 is a broken away oblique diagrammatic view of the structures in the zone 5A5A of FIG. 4.

FIG. 6 is an enlarged oblique and sectional view in zone 6A of FIG. 1 of a detail of the drum assembly 70.

FIG. 7 is a perspective view of a portion of the drum assembly of apparatus 220 of FIG. 5 in zone 7A.

FIG. 8 is a diagrammatic sectional view of a burner assembly 140, in zone 8A of FIG. 2 and 8B of FIG. 5.

FIG. 9 is a diagrammatic scale presentation of a transverse section through drum 110 rotated counterclockwise 120 (as seen from right side of FIG. 7) from the position shown in FIG. 7.

Patented Sept. 3, 1974 DESCRIPTION OF THE PREFERRED EMBODIMENTS The apparatus 20 according to this invention comprises a shell assembly 21, an agitating and transport assembly 22, a heating assembly 23 and a roller assembly 24 in co-operative combination.

The shell assembly 21 comprises a rigid frame 25 and a plurality of walls 30. A shell chamber 40 and a stack chamber are enclosed therein. The frame comprises a straight rigid left front vertical member 26, a straight rigid right front vertical pier 27, a straight vertical rigid right rear vertical pier 28 and straight rigid left rear pier 29. The left and right front piers 26 and 27 are joined by rigid straight horizontal beam members; i.e. to front side horizontal beam member 41 and bottom front side horizontal beam member 42. The rear vertical piers 28 and 29 are joined by rigid straight horizontal beam members, top rear side beam member 45 and bottom rear side beam member 46. A rigid triangular left truss 47 is firmly attached to the top of left front pier member 26 and left rear pier member 29 and a rigid right truss 48 is firmly attached to the top of right front pier member 27 and right rear pier member 28. A rigid straight semi-cylindrical, upwardly convex roof crest beam 43 extends from the top of the left truss 47 to the top of the right truss 48.

The walls of assembly 30 are rigid imperforate and insulating and firmly join these frame members and provide rigidity thereto. The left vertical end wall 31 is a rigid plate firmly joined to the left front and left rear piers 26 and 29. The second or right vertical end wall plate 32 is a rigid flat plate joined firmly to the right front pier 27 and the right rear pier 28. A front vertical wall 33 comprises a rigid plate joined to the front horizontal members 41 and 42 and a rear vertical wall 34, like 33, is a rigid plate firmly joined to the rear horizontally extending members 45 and 46.

Front sloped roof member 35 is an imperforate rigid insulating plate attached firmly to the bottom front edge of crest member 43 and to front horizontal beam 41 and to the front portions of the left truss 47 and right truss 48. A similar rear roof member 37 is an imperforate rigid insulating plate attached firmly to the bottom rear edge of crest beam 43 and to the top beam member 45 and rear portions of trusses 47 and 48. A first bottom sloped wall section 36 is firmly attached to the front bottom beam 42 and extends downwardly and inwardly therefrom. A rear bottom sloped wall section 38 is firmly attached to the rear bottom beam stringer 46 and extends downwardly and inwardly thereof. A shell chamber 40 is located between the walls and sections 31-38. It is within this shell chamber 40 that the agitating and transport assembly 22 is located.

A stack 50 is operatively connected to the chamber 40. That stack chamber is defined by a left vertically extending left wall 51, a vertically extending right wall 52, a front vertically extending wall 53 and a rear vertically extending wall 54. The walls 51-54 are joined at the top by an imperforate top wall 55 and imperforate, except for the opening of tube 46. An input tube 56 joins the right wall 52. The orifice of that tube 56 joins with the stack chamber. A fan casing 57 is firmly attached to the left wall 51 and supported on the roof 55.

A fan inlet opening 58 is located in the stack roof 55 and a fan outlet opening 59 is connected thereto. The stack opening 59 connects the shell chamber 40 to the stack chamber 49.

The agitating and transport assembly 22 comprises an auger assembly 60, an intermediate drum unit 70, an outer drum unit 80, a drive assembly 95 and a discharge assembly 90 and chute 100 supported on the shell assembly 21.

The auger assembly 60 comprises a helical auger blade 61, shaft 62, sprocket 63 and trough 64. The helical flat blade 61 is firmly attached to a horizontal shaft 62. The shaft in turn is firmly attached to a driven sprocket 63. The sprocket 63 is connected to and driven by a drive chain 69 and serves to rotate the shaft 62. The auger is located above and within imperforate semi-cylindrical trough 64. The auger is provided with rigid flat flights 65 and 66 the lengths of which extend lengthwise of the auger and also, being fiat, the widths of each flight extend radially along the width of the auger blade 61 and each fight is affixed to that blade. Shaft 62 is rotatably supported by a right bearing 67 in a right-hand wall 32 and on a left bearing 78 in the left vertical shell wall 31. Blade 61 is perforated.

The intermediate drum assembly unit comprises an intermediate hollow drum 71 below described which is supported on a horizontally extending rigid axle 72. The horizontally extending axle 72 has, firmly attached thereto, a driven sprocket 78 at its left end and a drive sprocket 73 at its right end. The axle 72 is rotatably supported on a bearing 75 in the left-hand shell wall 31 and in a bearing 76 in the right shell wall 32. Rigid spider frames 74, 74' and 74 are firmly attached to the interior of the intermediate shell 71 and to the axle shaft 72 along the length thereof. I

A chute 100'extends downwardly from the upper left wall at level of bottom of auger shaft 62 to below the top of the outer drum 80. Side walls 101 and 102 and end wall 103 define the chute chamber 104; chamber 104 extends from a semi-circular upper chute inlet orifice 105 located in wall 31 above the bottom of shield 64 and below shaft 62 to a chute outlet orifice 106 which extends from above shaft 73 to between the top and bottom of shell 71.

The outer drum 80 comprises an outer hollow cylindrical shell 81 and a plurality of rigid like spiders 84, 84' and 84" each of which spiders are at one end firmly attached to the interior of the shell 81 and at the other end to the axle 72.

The drums 70 and 80 are concentric; each is formed of a perforated and corrugated steel sheet with corruga tion as 107 on sheet 70 and 108 on sheet 80 arranged in a helical form. The helical corrugations extend to the right and downward on the rear side of the drum 70 and extend in the opposite direction; i.e. to the left and downward on rear side of the outer drum 80.

Each of the intermediate drum 70 and the outer drum 80 is made of corrugated and steel sheet metal 0.060 inches thickness, 117 and 118 respectively, perforated with circular holes as 120 of 0.010 inch diameter extending radially through such sheet. The centers of these holes are arrayed over the sheet of which the drum is formed as equilateral triangles with A inch between the centers of each of the neighboring holes. The corrugations of the sheet of which the drum is formed are 2 /2 inches between crests of the corrugations and the corrugated sheet measured parallel to the longitudinal axis of the drum and the radial distance from the top of the crest, as 123 and 123' to the bottom surf-ace of the adjacent trough, as 124 of the corrugations is /2 inch, which distance includes the thickness of the sheets as 117. The shape of the corrugations is that of a sine curve.

The helical crest to helical crest distance of each corrugations in the drum wall along the longitudinal axis of the drum 70 of the helical corrugations is five inches in the large drum 80 and a smaller distance about 3 inches in the 24 inch diameter drum 70.

The drive assembly 85 comprises in operative combination an electric motor 86 which drives a main sprocket 87. The main sprocket 97 is operatively connected by a chain drive as 88 to that sprocket and to the drive sprocket 78 on the drum axle 72. The driven sprocket 73 which is firmly attached to shaft 72 turns with shaft 72 and serves to drive the sprocket 63 on the shaft 62 through the drive chain 69 therebetween and operatively connected thereto and so serves to drive the shaft 62 for auger assembly 60. A drive sprocket 87 on the motor 86 is connected by a drive chain 89 to the drive sprocket 94 of the discharge assembly 90.

The discharge assembly comprises a helical conveyor 91, a chute 93 and a drive sprocket 94. The conveyor 91 operates at the bottom of the V-shaped chute formed at the bottom of chamber 40 by the sloped walls 133and 134. Chute 93 is a semi-cylindrical upwardly concave steel trough; its top edges connect to the bottom of wall 134 and to the bottom of wall 134 and are firmly attached thereto as by welding. Chute 93 is formed of rigid steel imperforate sheets such as are walls 31-35.

The front bottom wall section 36 of shell assembly 21 comprises a front upper heater frame section 132 and a front bottom sloped wall section 134. Some parts of the heating assembly 23 are supported in the upper front heater frame assembly 132. The rear bottom wall section 38 of the shell assembly 21 comprises a rear upper heater frame section 131 and rear bottom sloped wall section 133. Wall sections 133 and 134 are imperforate rigid steel plates. The rear heater frame section 131 shown in FIG. 5 comprises a series of vertical frame elements, as 135 and 137, each of which is firmly attached at its top to the horizontal beam member 46 and at its bottom to the top of the plate 133. A burner plate opening 136 is located between each of the frame members, as 135 and 137, and a burner screen plate 141 is located in such an opening and firmly attached to those frame members. Sections 36 and 38 are the same for embodiments 20 and 220.

A plurality of like openings 136A, 13613 and 136C, each like 136, are located in rear upper heater frame section 131 between the top of the plate 133 and the rear beam member 46 within the rear wall section 38 of the shell assembly 21. Front upper heater frame section 132 is a like structure to section 131 for the heater elements and is similarly attached to and located on the front sloped bottom wall section 134 and front side beam member 41 and has similar openings as 136E therein.

The burner screen plates as 142 fill all the openings as 136 and 136E in the bottom wall sections 131 and 132.

The heating assembly 23 comprises 40 like burner assemblies, as A and 140B, twenty in the heater frame elements of rear frame section 131 and twenty in the heater frame elements of front frame section 132. Each burner assembly comprises a porous ceramic burner screen plate 141, a burner connector pipe 142, a gas sup ply line 143 and an outer flame chamber wall 144. The

burner connector 142 is a standard L-shaped sturdy heat resistant cast iron nozzle which connects at its bottom to a gas line 143 in a conventional manner and at its top to the chamber and is attached to wall 144, gas line 143 running the length of chamber 40 on the outside thereof on the front of the chamber 40 and another like line 143A at the rear outside of chamber 40. Each gas line as 143 is connected to a plurality of burner connectors, as 142. Each burner is attached to the rigid outer flame chamber or plenum Wall 144. Wall 144 with the burner screen plate 141 outlines a flame or burning chamber 145. A pilot light 146 may be located in each flame chamber, as 145 to provide ignition as needed in conventional manner or ignition may be effected by.a torch at the screen plate 141. The burner screen plate 141 is made of a refractory porous material with holes about inch diameter which provides that the flame developed by burning of the gas provided by each gas line, as 143 provides flame temperatures within the plenum chamber 145 and causes the ceramic screen plate to glow red visibly, but avoids the production of any flame within the chamber 40. The screen plate 141 is sufficiently porous that the hot combustion gases formed by the combustion of the gas from line 143 and 143A heat the plate, and also pass through that plate into the chamber 40.

Each of the forty burners, as 140A, burns sufficient gas to provide a total of 2,400 B.t.u. per hour, or a total of 960,000 Btu. per hour.

The fan 147 which is located in the fan casing 57 is a portion of the heating assembly inasmuch as it provides the draft that helps draw the hot combustion gases provided by the burning assembly through the porous plate and through the chamber 40. Fan 147 is operatively connected to a motor 148, one horsepower electric motor. The motor 96 of the drive assembly 95 and the fan motor 148 are attached to conventional 110 volt A.C. electric power source. Motor 96 is supported on a frame 96A which sets on ground and the fan 147 is supported in the fan casing 57. Fan 147 provides a vacuum of about 12 inches of water during operation of the assembly 20.

A rigid cylindrical conduit extends from right wall 51 of stack 50 upward and to the right and is open upwards at its right end, at its lower end conduit 151 is open into the stack chamber 49 and firmly fixed to the vertical wall 51.

In operation the cereal grain, e.g. milo, to be treated is fed into the top opening of tube 56 and the fan 147 drives the exhaust moisture laden air, treated and heated as below described, up and out of fan outlet 59.

Grain to be heated falls through stack chamber 49 from the tube 56 into the horizontal helical auger or conveyor blade 61 and into the upwardly open semi-cylindrical trough 64. The blade 61 is perforated and fits loosely in trough 64.

The drive assembly 85 drives the sprockets 63 and 73 in a counterclockwise direction as seen from the right. Accordingly the grain added to the trough and auger blade is moved leftward in trough 64 by the rotated helical auger 61 to the left end of the trough 64. At the left end the heated grain falls down the chute 100 and then moves rightward therefrom along the intermediate helically grooved and perforated drum 70, rotated by motor 86, to the right end thereof; at the right end of drum 70 the heated grain falls to the lowermost or outer rotating perforated drum 80. The grain then moves from the right to the left along the rotated drum 80 and falls downward at the left end thereof. During such longitudinal movement of the grain leftward and rightward of chamber 40 the grain is tumbled and exposed to the hot gases that move through the orifices in the drums 70 and 80 as well as countercurrently of the hot gases passing burning assemblies, as 140 to the fan 147 along the lengths of the drums 70 and 80.

Parallel crushing rolls 158 and 159 each ten inches in diameter and 18 inches long are rotatably supported in chamber 40 and driven by a roll motor 160 through a drive pulley, as 161, belt 163 and driven pulley 162; the rolls are supported on frames therefor, as 164 and 165, that are firmly attached to the frame 25.

The heated and dried grain that falls from the left end of drum 80 drops into the slot between rolls 158 and 159 and is crushed and flaked. Because of the removal of water theretofore effected from such grain in the apparatus 20, the grain skin is brittle and the interior thereof is expanded by vaporization of the moisture theretofore entrapped in the grain kernel: on entry of such grain between the surfaces of the driven rolls 158 and 159 there is a popping action due to such entrapped steam in the still highly heated grain kernel; the resultant rupture of the thus treated grain product allows cycling of all such entrapped steam as a heating agent for other grain particles in the apparatus and, also, allows that during the time of further travel of the thus ruptured grain particle along the discharge conveyor 91 the moisture from such grain particle is discharged from the interior of sac-like particles as well as from the exposed surface of theretofore moist surfaces; such liberated moisture is thus removed from the theretofore unexposed interior surface of such grain particles. The crushed grain passes from between the rolls 158 and 159 to the discharge conveyor 91.

The discharge conveyor 91, driven by the drive chain 89 drives the thus treated grain rightwardly along chute 93 to a discharge spout 169 whereat the treated grain is collected.

The walls and roof members and bottom wall sections of shell 21, with the closure of the burner plate openings 136 by the burner plates form a completely closed chamber except for the small openings for bearings and dis charge as at spout 169. The fan 148 accordingly acts effectively to stimulate gas flow through the burner screen plates, as 141. All openings as 136 are completely filled with burners located on frames 131 and 132. Natural gas is used for heat; the burners are set to burn so that the oxygen in the burning air passing through the burner is substantially completely exhausted; i.e., as exhausted as much as the flame in the burners can provide. Accordingly, a non-oxidizing or reducing hot gas, at a temperature over 400 F., but less than carbonizing temperature moves counter-current to the tumbled grain passing through apparatus 20. The hottest gas and grain portions are at the bottom of apparatus 20'; the heating gas becomes successively cooler as it moves in countercurrent fashion through the drums 80 and 70' and assembly and out of the stack 50 due to evaporation of moisture from the grain and the relatively low temperature of the grain fed to apparatus 20.

The left to right length of the apparatus 20 is nine feet from the left end of that apparatus to its right end.

The r.p.m. of the drum 80 is 12 rpm. This velocity is snfiicient to keep the material in the drum well agitated and provide access of the heating gases thereto. More particularly, the drive motor 86 runs at 1725 rpm. A pulley wheel 187 provides for about a 10 to 1 reduction and the gear reducer gives about a 15 to 1 reduction additional for shaft 72.

The trash which is usually found in the grain is found to be carbonized at discharge of the treated grain. Accordingly, there is no oxidizing situation in the system following the burning so that the hot gases are, as above described, substantially non-oxidizing and there is no flame problem by this. This apparatus treats 2 tons of milo per hour, such milo fed has a moisture content of 10 to 15 percent by weight and is discharged at less than 0.03% moisture by weight.

The diameter of the drum '70, which is made of the same sheet material as the drum 80, is approximately 24 inches. There is an opening of 6 to 12 inches between the right-hand end of the drum and right shell wall 31. The drum has an end with less than six inches from wall 31.

The shell 21 is 8 feet high at the crest beam 43 (from ground at bottom of piers 25, 26, 27, 28 and 29) and is 42 inches wide from front to rear at its widest point, which is at the level of the axle 72. The bottom of the burner plates are 12 inches below the bottom of the drum 80; the plates 141 are 21 inches high and the outlet of the burner pipe 142 is in the middle of the wall 144: wall 144 and plate 141 are each 6 inches wide: axle 62 is 31 inches above axle 72; sprocket 94 is 52" therebelow.

Helical auger blade 61 is perforated with circular holes to allow free flow of heated gas therethrough. The diameter of such holes are about three inches and the helix diameter is about 16 inches and certainly provide no obstruction to the flow of hot gas therepast.

This is a low pressure system (as evidenced by the relatively small size of the fan that provides the driving energy for the system). The oxygen content of the gas 7 in the tower is so low that there is no flame near the grain thus treated.

The burner assemblies 140 each have on their internal discharge orifice a ceramic wall 141 with a large number of small perforations. This provides for heating of gas and a heat reservoir but substantially complete destruction of any flame.

In the embodiment of invention 220 (a) the drums 70 and 80 are substituted for by a drum 110 and (b) the discharge assembly 90 is substituted for by a mesh system 290 for the discharge assembly 90, and (c) the stack 50 is moved from the right-hand position on assembly 21 shown in FIG. 1 to the left-hand position shown in FIG. 4 and the helical auger 60 is made with anopposite direction of helix motion.

In the embodiment 220 the drum 110 is made of 3 semi-cylindrical rigid elements each corrugated and perforated. The corrugations in elements of drum 110 are circular. The shape of the corrugations; i.e. the distance between crests and height of the corrugations are the same as for elements 70 and 80 and is illustrated also in FIG. 6. The center line 191, 192 and 193 of each of the semi-cylindrical shell elements as 111, 112 and 113, respectively is offset from the center line 190, which line is located at the intersection of the diameters of such shells. This offset is along the direction of the diameter of each such shell (as diametral line from points 171 to 181, from points 172 to 182 and from point 173 to 183 for each of shells 111, 112 and 113, respectively). The amount of this offset is one-half the distance of the gap 184, 185 and 186, respectively at each of lips 181, 182 and 183 from the adjacent shells 113, 112 and 111, respectively. The angles that each of these diameters make with each other across the outer line 190 is the same; i.e. 120 where there are 3 such overlapping ele ments, as shown in FIGS. 4, 7 and 9. Spiders as 274 and 274', 284 and 284', support the elements 111, 112, 113 on shaft 72.

In the shell structure provided by drums 70 and 80, the perforations 120 provide for some heat transfer by contact of gas and grain particle. However the area of such holes is only ten percent of the area of the surface of the drums, 70 or 80 and such holes are tangential to the drum surface. Splitting the drum 70 into several scoop portions as in FIGS. 4 and 7 and 9 provides that gases produced by the burners be positively scooped and pumped into direct contact with all the grain directly rather than through effecting heat transfer through 90% of the drum thickness and with the stream of hot gases passing longitudinally through a transverse section of the volume of drums 70 or 80 of which only a portion (of such transverse section) is occupied by the grain to be heated at any one moment.

The structure of embodiment 220 provides that the at least the major portion of rising column of gas provided by the heating assembly 23 in embodiment 220 is all intercepted by the scoop action of the drum 110 and such interception is accomplished substantially continuously.

As shown in FIG. 9 which is drawn substantially to scale with a 26 inch diameter of drum-element 111, 112

and 113 and a 3 inch radial spacing 119, when the drum 110 is sufficiently full, on rotation of that drum in direction 129, two of the three lips, 182 and 181 will usually be blocked by the mass of grain 175 while the third lip 183 would be directing gas tangentially into the mass of grain. With the improved gas liquid contact provided by the drum 110 there is a more uniform heating of the grain independent of the rate of through-put of the treated solid; substantially all of the heated gases pass into direct contact with all of the grain and the grain travels in a continuous series of vertically extending curtains through which heated gas is continuously passed.

The discharge assembly 290 used in embodiment 220 comprises a mesh or screen support plate 152, an endless flexible metal mesh or screen 153, and drive rollers 154 and 155. The flexible mesh or screen 153 is driven by a motor 65A through the thereby driven mesh drive rollers 154 and 155. Crushing rolls 258 and 259, corresponding to rolls 158 and 159, are located at the discharge end of the screen 153. The discharge assembly 290 is used when large amounts of stem and leaves and like material (usually referred to as trash) are present in the grain treated: the flexible metal screen 153, which is 1 foot wide and of about spacing between wires of the mesh serves to clear the plate, 152 therebelow which is. 1 foot 2 inches wide as well as transport the heated and dried grain (usually of A; to 4 diameter) while the plate 152, which is a smooth flat topped plate supports the grain. The plate 152 is firmly attached to shell frame 25; the walls 133 and-134 extend centrally of the edges of the plate 152 and are attached to the top surface thereof. The jamming effect of trash and any carbonized leaves, stems and the like on helical screw conveyors is thereby avoided. The crushing rolls 258 and 259 are illustrated as located at the discharge end of the screen 153 with a roll hood 260 thereover and flexible rubber strips 261 and 262 that engage the rolls 258 and 259 to prevent entry of air into the chamber 40 within the shell assembly 23 past those rolls which might offset the reducing flame produced by heating assembly 23.

The rolls 258 and 259 are preferably positioned within the chamber 40 as are rolls 158 and 159 to provide for crushing of the heated grain between the drum 110 and the discharge assembly 290 as it is within the scope of this invention that the drum assembly 110 be used as shown in FIG. 10, for embodiment 320 with the shell assembly 21 and rolls 158 and 159 of roller assembly 24 in the shell chamber 40 between the discharge of the drum assembly 110 and the discharge conveyor 290 or and operatively connected to drive assembly 85 and heater assembly 23 as above described for embodiment 20 and 220.

In the above description of the apparatuses and process the terms left and right refer to the left and right side of FIGS. 1 and 4, and the term front refers to the side of the apparatuses 20 and 220 closest to the viewer and the term rear refers to the side of such apparatuses distant from the viewer in those figures.

The temperature of the gases exhausted from stack 50 in embodiment 20 is over 150 |F., and about 175 F. when two (2) tons of mile at 10%15% moisture and less than 1% trash is fed thereinto and conventional natural gas of 900 to 1,200 B.t.u./cu. ft. is burned at a suflicient rate of cubic feet per hour to provide 900,000-960,000 B.t.u./h.r. by the totality of heating nozzles of heating assembly 23; the flames produced thereby are reducing flames as visually observed by the reflected orange color (of the flame) in the surface of nozzle 142 near the entry thereof into wall 144 and by the absence of any carmelizing odor or burnt smell or appearance of the product at spout 169. The thus flaked and dried milo is digestible by and palatable to cattle as observed by their consumption and conversion thereof. The exhaust temperature is lower when the drum 110 is usedin embodiment, as 220 or 320, than in embodiment 20.

In the drum 110 the diameter across edge 171 to 181 and 172 to 182 and 173 to 183 is 26 inches, eachof the gaps 184-185 and 186 is 3 inches measured radially from longitudinal axis of the straight rigid cylindrical shaft 72; the drum 110 may be sloped downward inch per foot towards its discharge end along length of shell assembly 21 and its left and right ends extends to one foot of each of end walls 31 and 32 of shell 21 and discharges the heated grain at its leftend into rolls assembly (in embodiment 320) and is fed at the right end by a chute as A from the upper preheating auger assembly 60. The tangential extent of the lips 181, 182 and 183 of the rigid semicircular elements as 111, 112 and 113 (past elements 113, 111 and 112, respectively) and loading of drum by mass 175 of grain in segments 111, 112 and 113 is sufiicient to prevent discharge of the material carried by such drum from the more radial and tangentially extending lips or edges, as 181, 182 and 183 while permitting discharge of the milo in drum 110 from the less radial and less tangentially extending edges, as 171, 172 and 173 to the interior surface of the drum segment radial thereto as 112, 113 and 111, respectively. Such action creates smoothly flowing masses or curtains of such particulate material through the, interparticulate spaces of which masses or curtains the hot gases produced by the burner assembly 24 is always periodically, regularly, evenly and usually continuously forced by the scoop action of the drum 110 while rotating in the direction (129) of tangential extension of the more radial edges (as 181, 182, 183) of that drum (110). Apparatus 20, 220 and 320 may treat other cereal grains than the milo above referred to in the exemplary embodiment of process.

The amount of grain fed to the input 56 is controlled by a variable speed auger 356: this also serves to regulate the grain temperature.

I claim:

1. Process of treating moisture containing cereal grain comprising steps of (a) forming a hot non-oxidizing gaseous medium at a temperature in excess of 400 F. but less than carbonizing temperature in the bottom of a substantially completely closed heating chamber while (b) adding a mass of grain to the top of said chamber while moving said grain consecutively in vertically extending paths and then in longitudinally extending horizontal paths through said chamber to the bottom thereof while tumbling said grain and expanding the grain skin by vaporization of moisture entrapped in the grain kernel, and then (c) crushing and flaking the thus heated grain and producing ruptured grain particles and exposing theretofore unexposed surface of interior portions of said grain while in said heating chamber, and

(d) discharging steam from said exposed surfaces of the crushed grain and passing said steam as a heating agent to other grain particles in said chamber prior to their crushing together with said hot non-oxidizing gaseous medium transversely and countercurrent to said paths of movement of said grain and thereby heating said grain and vaporizing moisture within said grain, and wherein substantially all of the heat of the hot non-oxidizing gaseous medium of said steam are continuously passed to said grain fed into said chamber.

2. Process as in claim 1 wherein the grain travels in a continuous series of vertically extending curtains through which heated gas is continuously passed.

3. A process as in claim '1 wherein the hot non-oxidizing gaseous medium is at a temperature over 400 F. at the bottom of said chamber and is discharged from the top thereof at about F.

4. Process as in claim 3 wherein said hot non-oxidizing gaseous medium is added to said chamber at rate of 900,000 to 960,000 B.t.u. per hour per 2 tons of grain at 10l5% moisture fed into said chamber and the fed grain has moisture content of 10-15% and is discharged at below 0.3% moisture from said chamber.

5. Process as in claim 4 wherein particles of said grain are expanded prior to crushing and the crushing step is concurrent with a popping of said grains.

- References Cited UNITED STATES PATENTS 1,058,291 4/1913 Dennis 99-80 PS 1,949,427 3/1934 McComb 99-80 PS 322,252 7/1885 Bunnell 34-33 353,924 12/1886 Cormack 9980 PS RAYMOND N. JONES, Primary Examiner 

